It passed unanimously in a 4-0 vote. HB 175 seeks to ban solitary confinement for inmates under the age of 18, pregnant women, and those with known serious mental illnesses.

"There is a growing body of literature about the disturbing use and effect of solitary confinement on people with mental illness. This bill will put an end to this inhumane and outdated practice in New Mexico,” Maestas said. “In addition to violating human rights, it's costing taxpayers millions."

House Bill 175 also introduces new reporting requirements for correctional facilities so that county commissions can be kept apprised of the number of inmates held in solitary confinement as well as the reasons they are being held there. The bill also requires correctional facilities to report all monetary settlements paid out to inmates and former inmates as a result of lawsuits filed against the facility or its employees.

Inmates in solitary confinement can spend up to 23 hours a day isolated in windowless cells. Solitary confinement can have devastating psychological effects on inmates. Studies have indicated that it can exacerbate mental illness, trigger new mental disorders, and lead to an increased rate of suicide.

In addition to the psychological costs, there are public safety and fiscal problems with solitary confinement. The bipartisan Commission on Safety and Abuse in America’s prisons found that acts of violence in prisons often increased with the use of solitary confinement. It can also cost almost three times as much to house an inmate in solitary versus in the general prison population. President Barack Obama banned solitary confinement for juvenile offenders in federal prisons in 2016.

In New Mexico, the use of solitary confinement has provoked expensive lawsuits. In 2013, Doña Ana County paid over $15 million to a man who spent 22 months in solitary confinement after being arrested for driving under the influence, which carries a 90 day maximum penalty.